Answer:
![y=\text{ 230 streetlights}](https://img.qammunity.org/2023/formulas/mathematics/college/jdd3vaqqfh1ucrilaxofu5p0mfiyz9smkt.png)
Explanation:
This situation can be represented as a linear equation since it has an initial value and a constant rate of change per week. Remember that linear equations are given as:
![\begin{gathered} y=mx+b \\ \text{where,} \\ m=\text{ constant rate of change} \\ b=\text{ initial value} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/g01e5qavdk0oqeikk2drjn70ypc4jwgl5u.png)
Then, to determine how many streetlights the city will have at the end of 31 weeks, substitute x=31 into the following equation;
![\begin{gathered} y=3x+137 \\ y=3(31)+137 \\ y=\text{ 230 streetlights} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/2p87zxj8u418hem6u07eoxk0alzwlplwiz.png)